Helicopter propeller rotor



FIG. 1 is a top view of a helicopter propeller rotor;

FIG. 2 is a side view of the helicopter propeller rotor;

FIG. 3 is a rear perspective side view of the helicopter propeller rotor; and,

FIG. 4 is a front perspective side view of the helicopter propeller rotor.

Broken lines are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a helicopter propeller rotor, as shown and described. 